Thanks.
The examples at https://gohugo.io/extras/crossreferences/ go in the right direction.
Now I have the markdown code:
[some link text]({{< relref “page2.md” >}})
which is converted to a html href as expected: <a href="/pages/page2/">some link text</a>
However, I would like to have a shorter syntax with as less boilerplate as possible, ideally like
[page2] converted to <a href="/pages/page2/">page2</a>
Is there such a simple syntax supported? If not, what would be the best way to implement it? (I plan to support some other syntax deviations from standard markdown anyway, such as todolists: https://github.com/blog/1825-task-lists-in-all-markdown-documents).